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Molecular dynamics simulations are performed for CuZr metallic alloys to study the structural and dynamical features for glass forming ability ͑GFA͒. Our analysis shows that in CuZr metallic system, although ͗0,0,12,0͘ icosahedral clusters are important, some Zr-centered clusters such as ͗0,1,10,4͘ and ͗0,1,10,5͘ play a key role in slowing down the dynamics. It is found that these Zr-centered clusters are intrinsically slow and fundamentally determine the stability and slow dynamics. Due to the strong spatial correlation between ͗0,0,12,0͘ and Zr-centered clusters, their relative population influences the dense packing and dynamics in metallic glasses, and further the GFA.

We report that bulk metallic glasses (BMGs) with large plasticity can be obtained in conventional brittle BMGs by a shrink-fit metal sleeve. The mechanical performance especially the plasticity in the Zr41.2Ti13.8Cu12.5Ni10Be22.5 BMG with a shrink-fit copper sleeve is much enhanced. The approach results in the formation of the highly dense and frequent interacting and arresting events of shear bands and is the origin of the observed large global plasticity. The results present another simple step toward toughening the inherently brittle BMGs.

Zr/Nb-based bulk metallic glass (BMG) with a composition of Zr 48 Nb 8 Fe 8 Cu 12 Be 24 was formed in cylindrical shapes 8 mm in diameter by the quartz tube water quenching method. The formation and acoustic, thermal, mechanical, and elastic properties of the BMG were investigated. The BMG exhibited excellent glass-forming ability, high thermal stability, and excellent mechanical properties.

We report the fabrication and study of thermal stability of atomically thin ZrCu-based metallic glass films. The ultrathin films exhibit striking dynamic properties, ultrahigh thermal stability, and unique crystallization behavior with discrete crystalline nanoparticles sizes. The mechanisms for the remarkable high stability and crystallization behaviors are attributed to the dewetting process of the ultrathin film. We demonstrated a promising avenue for understanding some fundamental issues such as glassy structure, crystallization, deformation, and glass formation through atomic resolution imaging of the two dimensional like metallic glasses.